Harmony Wonder is finally 18 and her friend Lexi Lore is envious that Harmony's parents are throwing her a sweet 18 birthday party. The friends are hanging out on the couch when Harmony's stepbrother Rion King comes in to give his sister a card. The card includes a coupon for a free fuck, which Rion claims isn't for his stepsister but for her friend. Lexi is game, so she agrees to help Rion out of his dry spell with a handie. Harmony gets a glimpse of her stepbro's big dick and leans back to masturbate. The trio is interrupted by Harmony's dad.
Later, after the party Rion approaches Lexi and suggests that they should finish what they started. Harmony tries to say they shouldn't do it, but Lexi is quick to get on her knees and start sucking Rion off. Lexi is once again nearly caught in the act by Harmony's dad, but he is loud enough that Lexi and Rion have enough time to get their clothes back in order.
Lexi and Harmony are alone in the living room later when Lexi gives Harmony another piece of cake and then rubs frosting on her friend's nipples. The girls are soon making out under the guise of cleaning up frosting from each other's nipples and then pussies. Rion walks in on them as they indulge in a full-blown 69. Lexi spots her friend's brother first and beckons him close so she can suck his dick. Then she beckons for him to fuck his stepsis. Once Harmony has had a taste of the D, she doesn't want him to stop! That kicks off a threesome that doesn't end until both girls have gotten off and Rion has covered their faces in jizz. Just as they're winding down, they are finally busted in truth by Harmony's dad.